/* ===========================================================
 * TradeManager : An application to trade strategies for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2011-2011, by Simon Allen and Contributors.
 *
 * Project Info:  org.trade
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Java is a trademark or registered trademark of Oracle, Inc.
 * in the United States and other countries.]
 *
 * (C) Copyright 2011-2011, by Simon Allen and Contributors.
 *
 * Original Author:  Simon Allen;
 * Contributor(s):   -;
 *
 * Changes
 * -------
 *
 */
package org.trade.core.lookup;

import java.util.Vector;

/**
 * @author Simon Allen
 */
public class LookupService {
	//
	// Private Attributes
	//
	private static Vector<LookupServiceProvider> _providers = new Vector<LookupServiceProvider>();

	static {
		addLookupServiceProvider(new PropertyFileLookupServiceProvider());
		addLookupServiceProvider(new DBTableLookupServiceProvider());
	}

	/**
	 * Get the appropriate Lookup.
	 * 
	 * @param lookupName
	 *            String
	 * @param qualifier
	 *            LookupQualifier
	 * @param optional
	 *            boolean
	 * @return Lookup
	 * @exception LookupException
	 */
	public static Lookup getLookup(String lookupName,
			LookupQualifier qualifier, boolean optional) throws LookupException {
		Lookup lookup = null;
		// Loop through the registered providers and find and try to find one
		// that can provide the lookup
		int providersSize = _providers.size();

		for (int i = 0; i < providersSize; i++) {
			lookup = _providers.elementAt(i).getLookup(lookupName, qualifier,
					optional);

			if (null != lookup) {
				// Have found a Lookup - don't care if another provider can
				// provide it or not
				break;
			}
		}
		return lookup;
	}

	/**
	 * Method addLookupServiceProvider.
	 * 
	 * @param provider
	 *            LookupServiceProvider
	 */
	public static void addLookupServiceProvider(LookupServiceProvider provider) {
		if (!_providers.contains(provider)) {
			_providers.addElement(provider);
		}
	}

	/**
	 * Method removeLookupServiceProvider.
	 * 
	 * @param provider
	 *            LookupServiceProvider
	 */
	public static void removeLookupServiceProvider(
			LookupServiceProvider provider) {
		_providers.removeElement(provider);
	}
}
